This invention pertains to erodible material wear indicators and more particularly to brake lining or clutch pad wear indicators. At present, sound emitting and electrical wear indicators are commonly utilized in motor vehicle brakes. Sound emitting indicators have an inherent drawback related to necessity to exceed the diesel engine noise and cab acoustical protection. Electrical and hydraulic wear indicators have durability and cost efficiency shortcomings.
The subject vapor emitting wear indicator can be used on disc or drum brakes, vehicle clutches or anywhere else where there is a need to indicate an alarming level or point of material erosion. The novel material wear indicator overcomes the shortcomings of contemporary devices and simplifies manufacture, control and installation process with improved serviceability and increased cost efficiency.